Treehaus Audiolab’s New ‘A/Machines’ 300B Amp to Debut At Axpona 2024

That’s a lot of amp.

The new Treehaus Audiolab “A/Machines” 300B Amplifier is based on the company’s existing 300B amp simply called “The Amplifier”, which is inspired by the work of the legendary Susumu Sakuma. Featuring a four chassis mono design—amp/power supply + amp/power supply—the new “A/Machines” put out 6 Watts of pure SET power, which is more than enough in the right setting.

The A/Machines utilize large Simpson analog gauges, heavy 6mm aluminum plinths, crinkle powdercoat enclosures, and brass details throughout.

There are plenty of tasty parts inside (and out) including interstage and power transformers from Finemet Transformer of Japan while the Western Electric 300Bs are driven by a 10Y/801A.

The Treehaus Audiolab “A/Machines” 300B Amplifier will be making its world debut at Axpona 2024 in Room 1420 paired with what should be a familiar looking pair of Treehaus “Phantom of Luxury” field-coil loudspeakers.

The Treehaus Audiolab “A/Machines” 300B Amplifier retails for $39,000 (including all tubes).

Here’s the press release:


Treehaus Audiolab Brings “The A/Machines.”
New 300B Amplifier to Debut at AXPONA 2024…with a Fresh Batch of Cookies

March 21, 2024—Treehaus often avoids calling a product “The Best.” The world of audio is far too subjective to ever use such a term seriously. That said, the A/Machines are confidently one of the top five 300B Single-Ended Triode (SET) amplifiers ever produced. It is the culmination of over a decade of research, development, and testing of a myriad of amplifier designs and components. Yes, the origins predate the formation of Treehaus Audiolab itself.

Engineered and built by legend Radu Tarta, the foundation of the A/Machines is similar to our existing excellent 300B amplifier inspired by Susumu Sakuma. A 10Y/801A drives the famed Western Electric 300B through a Finemet-Core interstage transformer made for Treehaus Audiolab in Japan. The output transformer, also with a Finemet-Core, utilizes a non-traditional impedance loading which eliminates the typical darker, syrupy sound of most 300B designs. Coleman filament regulators on separate dedicated DC supplies provide ultra-clean heater current to the directly-heated tubes.

The A/Machines depart from this design by using 4 enclosures rather than 2. Each channel is two units: one amplification section and one power supply section. The ultimate layout for noise and channel separation. To keep it simple, we simply doubled the total tube-rectified power supply capacity compared to the existing design. Gratuitously, we utilized Finemet-Core chokes and massive G.O.S.S. Core power transformers. MIL-spec Amphenol umbilical cords and Cardas binding posts connect power and signal. Nothing was held back

The result is everything loved about our 300B amplifier, just more of it. More energy, more detail, more clarity, more nuance, more refinement, and still with plenty of SET magic. Six entire watts of it.

The A/Machines also debut a new visual design language offered by Treehaus Audiolab, inspired by early Klangfilm and Western Electric amplifiers. The A/Machines utilize large Simpson analog gauges, heavy 6mm aluminum plinths, crinkle powdercoat enclosures, and brass details throughout. A matching preamplifier, that goes to 11, demonstrates the design language on our existing preamplifier electronics.

If AXPONA attendees get a case of the munchies (we are in room 1420 after all), Treehaus Audiolab “Phantom of Luxury” field-coil loudspeakers will be shown in a new “Elm Cookies” finish, wired with Iconoclast SPTPC cabling.

Special Guests include Iconoclast Cable, and SME Limited Precision Turntables and Tonearms.

About Treehaus Audiolab

Audio Mania, the pursuit of best sound, is our design ethos. We find inspiration in technology from the golden ages of audio around the world, and reimagine it for the 21st century listener. Treehaus Audiolab was founded in 2017 in Connecticut.